Syringe filling and delivery device

ABSTRACT

A fluid transfer device for accessing fluid from vials and ampoules includes a cannula assembly including a cannula having a lumen therethrough connected to a hub having an open proximal end. A filling straw includes a proximal end, a distal end, and a passageway therethrough. The straw further includes a needle portion at the distal end and a shaft portion between the needle portion and the proximal end. A cutting edge is provided at the distal end of the needle portion for piercing a vial stopper. The cannula assembly is removably engaged with the filling straw so that the open proximal end of the hub is in fluid communication with the passageway of the filling straw. An elongate shield having an open proximal end, an open distal end and a side wall therebetween defining a recess in the shield. The shield is removably connected to the straw so that the shaft portion and the needle portion of the straw are contained within the recess. A seal plug having a proximal end and a distal end is provided. The seal plug has a distal position with respect to the shield wherein the seal plug projects distally outwardly from the distal end of the shield for telescoping movement from the distal position to a proximal position wherein the seal plug seals the needle portion to prevent unpressurized fluid communication between the passageway and the exterior of the shield.

CROSS-REFERENCE TO RELATED APPLICATIONS

This patent application is a continuation-in-part of U.S. patentapplication Ser. No. 681,253 filed on Jul. 22, 1996, which is acontinuation-in-part of U.S. patent application Ser. No. 245,934 filedon May 19, 1994 now abandoned.

FIELD OF THE INVENTION

The subject invention relates to a device mountable on a hypodermicsyringe or other fluid delivery device which enables access tomedication or injectable liquid in either glass ampoules or in vialshaving elastomeric closures and the subsequent delivery of medication orinjectable liquid.

BACKGROUND

A typical hypodermic syringe includes a syringe barrel with a mountingcollar for threadedly engaging the hub of a needle cannula. The hub andthe needle cannula are connected to one another or are maintainedseparately from the syringe barrel until shortly prior to use. In caseswhere the needle is maintained separately, the medical practitionerselects an appropriate needle assembly for the procedure being carriedout. The needle assembly is removed from its sterile package, and thehub of the needle assembly is threadedly engaged with the mountingcollar of the syringe barrel.

Liquid pharmaceuticals and other injectable liquids are often stored inrigid containers which can be accessed using a hypodermic syringe. Somecontainers for liquid pharmaceuticals are plastic or glass vials with anelastomeric closure that can be penetrated by the needle of a hypodermicsyringe. To access the liquid in a vial, the medical practitioner movesthe plunger of the hypodermic syringe in a proximal direction to drawinto the syringe barrel a volume of air substantially equal to thevolume of medication that is desired. The open distal end of the needleis then urged through the elastomeric closure of the vial, and the airin the syringe barrel is injected into the vial. The distal tip of theneedle and the vial engaged therewith are then pointed gravitationallyupwardly. The practitioner ensures that the distal tip of the needle iscovered by the medication in the vial by manipulating the needle and thevial with respect to each other. The plunger of the hypodermic syringeis then moved proximally to draw the medication through the needle andinto the chamber of the syringe barrel.

After withdrawing a desired dose of medication from a vial, the medicalpractitioner may inject the medication into either a patient, anothervial or into an injection site of an intravenous set or catheter. Thereis a trend toward needleless I.V. systems which do not require a pointedneedle cannula to piece the injection site of an I.V. set. There aremany systems that have injection sites covered by a pre-slit septumwhich can be accessed by a blunt cannula. Accordingly, after withdrawingmedication from a vial using a sharp needle the user must remove theneedle and install a blunt cannula if the medication will be used withan I.V. set. The user runs the risk of accidental needle stick using theneedle to draw the medication into the syringe and in the act ofremoving the needle to replace it with a blunt cannula. Also, there isthe potential of contaminating the components when they are installedand removed during the filling and delivery process. Accordingly, thereis a need for a device which will allow filling of a syringe from a vialhaving a pierceable stopper without the use of a very sharp needle andthe subsequent delivery of the medication to an I.V. set through a bluntcannula without having to handle or reshield sharp needles.

Plastic vials and elastomeric closures for vials are somewhat gaspermeable. Some pharmaceutical products will degrade rapidly in thepresence of even small amounts of gas. Hence, these pharmaceuticalstypically are stored in glass ampoules. The frangible end of a glassampoule can be snapped off to enable access to the medication storedtherein. The medical practitioner may withdraw the medication byinserting the tip of the needle on a hypodermic syringe into themedication stored in the ampoule. The plunger of the hypodermic syringeis then moved proximally to draw the liquid medication in the ampoulethrough the needle and into the barrel of the hypodermic syringe. Thehypodermic syringe may then be withdrawn from the ampoule and used insubstantially the manner described above. The ampoule typically is heldwith the open top gravitationally upwardly while the hypodermic syringeis being filled. This needle length required for ampoule filling maysubstantially exceed the length of the needle conveniently required forsubsequent use for injections. Likewise, the same or similar problemsexist where the medication obtained from an ampoule will be subsequentlyinjected into an injection site having a pre-slit septum since theneedle must be installed and removed from the syringe and the new bluntcannula installed. Thus, there are risks with accidental contaminationand needle sticks before the properly filled syringe and blunt cannulacombination are prepared.

SUMMARY OF THE INVENTION

The subject invention relates to a device for safety and efficientlyfilling a hypodermic syringe. The device may include a blunt cannulahaving opposed proximal and distal ends. The proximal end is configuredfor engagement with the distal end of the hypodermic syringe. Forexample, the proximal end of the blunt cannula may include projectionsfor threadedly engaging a luer collar at the distal end of the syringebarrel. The distal end of the cannula may be blunt and may be configuredfor selective mating with a prior art fitting of an intravenous line.

The device further comprises a vial access spike which has opposedproximal and distal ends and a communication passage extending axiallytherethrough. The proximal end of the vial access spike is releasablymounted in fluid-tight engagement with the distal end of the bluntcannula. For example, the proximal end of the passage through the vialaccess spike may be frictionally secured in fluid-tight engagement overthe distal end of a blunt cannula. The distal end of the vial accessspike defines a beveled tip that is sharp enough to pierce the rubberstopper of a vial, but preferably not sharp enough to pierce skinthrough incidental contact. The vial access spike may further include acap for selective sealing engagement over the proximal end of the spike.The cap may be unitarily connected to the vial access spike by a hingeor a tether. A hinged connection may be defined by an over-center hingewhich is stable in a fully open or fully closed position of the cap.However the over-center hinge will be biased at intermediate positionsto urge the cap into either the fully opened or fully closed position.

The device may further comprise a protective shield that can be mountedover at least the distal end of the vial access spike. The protectiveshield may have a slot to surround the hinge or tether. The shieldprevents contamination of the beveled distal tip of the spike prior toinsertion into the vial.

The assembled blunt cannula, vial access spike and shield may bepackaged separately from the hypodermic syringe. Alternatively, theassembled blunt cannula and vial access spike may be mounted on andpackaged with the hypodermic syringe.

A hypodermic syringe that has the subject filling device mounted theretomay be filled by removing the shield from the vial access spike anddriving the beveled distal end of the vial access spike through the vialstopper. The hypodermic syringe and the vial may then be inverted, suchthat the liquid medication in the vial covers the distal end of the vialaccess spike. The plunger of the hypodermic syringe may then be pulledin a proximal direction to draw fluid into the syringe barrel. The usermay then separate the connected hypodermic syringe and blunt cannulafrom the vial access spike, and the connected hypodermic syringe andblunt cannula may be used in the conventional manner. The vial accessspike will remain in the vial, and the cap can be engaged over theproximal end of the spike to seal the vial for subsequent access.

A fluid transfer device for accessing fluid from vials and ampoules ofthe present invention comprises a cannula assembly including a cannulahaving a proximal end, a distal end and a lumen therethrough, and a hubhaving an open proximal end and a distal end joined to the proximal endof the cannula so that the lumen is in fluid communication with the openproximal end of the hub. A filling straw having a proximal end, a distalend, and a passageway therethrough includes a housing at the proximalend, a needle portion at the distal end and a shaft portiontherebetween. A ledge between the needle portion and the shaft portionis provided for limiting the depth of penetration of the needle portioninto a vial stopper. The housing includes a cavity in its proximal endin fluid communication with the passageway. A cutting edge at the distalend of the needle portion is provided for piercing a vial stopper.Structure is provided for removably engaging the cannula assembly withthe housing so that the open end of the hub is in fluid communicationwith the passageway of the filling straw and the cannula is within thecavity. A shield having an open proximal end, a distal end, and a sidewall therebetween defining a recess in the shield is removably connectedto the straw so that the shaft portion and the needle portion of thestraw are contained within the recess.

A fluid transfer device of the present invention comprises a cannulaassembly including a cannula having a proximal end, a distal end and alumen therethrough. A hub having an open proximal end and a distal endis joined to the proximal end of the cannula so that the lumen is influid communication with the open proximal end of the hub. A fillingstraw includes a proximal end, a distal end and a passagewaytherethrough. The straw includes a needle portion at its distal end anda shaft portion between the needle portion and the proximal end. Acutting edge at the distal end of the needle portion is provided forpiercing a vial stopper. The cannula assembly and the filling straw areremovably engaged so that the proximal end of the hub is in fluidcommunication with the passageway of the filling straw. A shield has anopen proximal end, an open distal end and a side wall therebetweendefining a recess in the shield. The shield is removably connected tothe filling straw so that the needle portion and substantially all ofthe shaft portion are contained within the recess; and a seal plug has aproximal end and a distal end. The seal plug has a distal position wherethe seal plug projects distally outwardly from the distal end of theshield for telescoping movement from the distal position to a proximalposition wherein the seal plug seals the needle portion to preventunpressurized fluid communication between the passageway and theexterior of the shield.

Another embodiment of the present invention includes a method fortransferring injectable liquid including the steps of:

(a) providing a syringe including a syringe barrel having an elongatecylindrical body defining a chamber for retaining fluid, an openproximal end, a distal end and a tip extending from the distal endhaving a tip passageway therethrough in fluid communication with thechamber, a stopper in fluid-tight slidable engagement inside the barreland an elongate plunger rod connected to the stopper and extendingproximally through the open end of the barrel;

(b) providing a syringe filling device comprising a cannula assemblyincluding a cannula having a proximal end, a blunt distal end and alumen therethrough, and a hub having an open proximal end and a distalend joined to the proximal end of the cannula so that the lumen is influid communication with the open proximal end of the hub; a fillingstraw having a proximal end, a distal end and a passageway therethrough,the straw including a housing at the proximal end, a needle portion atthe distal end and a shaft portion therebetween, the housing having acavity in its proximal end in fluid communication with the passageway, acutting edge on the distal end of the needle portion for piercing a vialstopper, the cannula assembly being removably engaged with the housingso that the open proximal end of the hub is in fluid communication withthe passageway of the filling straw and the cannula is within thecavity; a shield having an open proximal end, an open distal end and aside wall therebetween defining a recess in the shield, the shield beingremovably connected to the straw so that the shaft portion and theneedle portion are contained within the recess; and

a seal plug having a proximal end and a distal end, the seal plug havinga distal position wherein the seal plug projects distally outwardly fromthe distal end of the shield for telescoping movement from the distalposition to a proximal position wherein the seal plug seals the needleportion to prevent unpressurized fluid communication between thepassageway and the exterior of the shield

(c) connecting the syringe filling device to the syringe so that the tipis positioned within the open proximal end of the hub and the chamber isin fluid communication with the cannula;

(d) providing a vial having a pierceable septum and containing aninjectable liquid;

(e) removing the shield from the straw;

(f) piercing the pierceable septum of the vial with the needle portionof the filling straw to establish fluid communication between theinterior of the vial and the chamber of the syringe;

(g) withdrawing the desired amount of injectable liquid from the vialinto the chamber by moving the plunger rod in a proximal direction withrespect to the barrel; and

(h) withdrawing the needle portion from the septum of the vial; and

(i) reconnecting the shield to the straw so that the needle portion andsubstantially all of the shaft portion of the straw are contained withinthe recess of the shield; and

(j) moving the seal plug from the distal position to the proximalposition to seal the needle portion.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded perspective view of the syringe filling device inaccordance with the subject invention for accessing medication in anampule.

FIG. 2 is a side elevational view of the blunt cannula and vial accessspike of the subject invention.

FIG. 3 shows the filling device of FIG. 2 mounted to a hypodermicsyringe and accessing fluid medication in a stoppered vial.

FIG. 4 is a side elevational view similar to FIG. 3, but showing thehypodermic syringe and blunt cannula separated from the vial and thevial access spike.

FIG. 5 is a side elevational view similar to FIG. 2, but showing analternate vial access spike.

FIG. 6 is a cross-sectional view of the blunt cannula and vial accessspike of FIG. 5 taken along line 6--6.

FIG. 7 is a perspective view of the blunt cannula of the presentinvention and a syringe aligned for assembly.

FIG. 8 is an alternative embodiment of the present invention wherein theblunt cannula and the syringe barrel are integrally molded of one piececonstruction.

FIG. 9 is a side elevational view of the fluid transfer device of thepresent invention attached to a syringe.

FIG. 10 is a partial cross-sectional view of a fluid transfer device andsyringe of FIG. 9 taken along line 10--10.

FIG. 11 is a side elevational exploded view illustrating the assembly ofthe fluid transfer device of the present invention.

FIG. 12 is a cross-sectional view of the fluid transfer device of FIG.11 taken along line 12--12.

FIG. 13 is a side elevational view of the fluid transfer device attachedto a syringe barrel illustrating the shield being removed.

FIG. 14 is a side-elevational view illustrating the fluid transferdevice and syringe being used to withdraw injectable liquid from a vialhaving a pierceable stopper.

FIG. 15 is a side elevational view of the fluid transfer device andsyringe being used to withdraw injectable liquid from an ampoule.

FIGS. 16 and 17 illustrate steps in a method of use of the presentinvention between filling and dispensing of injectable liquid.

FIGS. 18-20 illustrate steps in another method of use of the presentinvention between filling and dispensing of injectable liquid.

FIG. 21 is a side elevational view of injectable liquid being deliveredto an injection site in an I.V. set using the cannula assembly of thepresent invention and a syringe.

FIG. 22 illustrates an alternative cannula assembly.

FIG. 23 illustrates a standard hypodermic needle.

FIGS. 24 and 25 are side elevational views illustrating an alternativeembodiment of the present invention.

FIG. 26 illustrates another embodiment of the present invention whereinthe cannula and the syringe barrel are integrally formed in one piece.

FIG. 27 illustrates another embodiment of the fluid transfer device ofthe present invention and a syringe.

FIG. 28 is an exploded cross-sectional view of the fluid transfer deviceand syringe of FIG. 27 taken along line 28--28.

FIGS. 29 and 30 are cross-sectional side elevation views having analternative embodiment of the present invention including a shieldhaving a movable seal plug.

FIGS. 31 and 32 are cross-sectional side elevation views having anotheralternative embodiment of the present invention including a shieldhaving a movable seal plug.

FIG. 33 is a cross-sectional view of the fluid transfer device of FIG.32 taken along line 30--30.

FIG. 34 is a cross-sectional side elevation view having still anotheralternative embodiment of the present invention including a shieldhaving a movable seal plug.

DETAILED DESCRIPTION

While this invention is satisfied by embodiments in many differentforms, there are shown in the drawings and will be herein described indetail preferred embodiments of the invention with the understandingthat the present disclosure is to be considered exemplary of theprinciples of the invention and not intended to limit the scope of theinvention to those embodiments illustrated. The scope of the inventionwill be measured by the appended claims and their equivalents.

The syringe filling device in accordance with the subject invention isidentified generally by the numeral 10 in FIGS. 1 and 2. Filling device10 includes a blunt cannula 12, a vial access spike 14 and a shield 16.Filling device 10 is for use with a prior art hypodermic syringe 18.Syringe 18 includes a syringe barrel 20 having a distal end 22, aproximal end (not shown) and a fluid receiving chamber 24 therebetween.The proximal end of syringe barrel 20 is open and slidably receives aplunger 26 in fluid-tight engagement with the cylindrical wall definingchamber 24. Distal end 22 of syringe barrel 20 includes an elongate tip28 having a passage 30 extending axially therethrough and communicatingwith chamber 24. The syringe preferably includes a luer collar 32concentrically surrounding tip 28 and includes an internal thread 34.

Blunt cannula 12 of syringe filling device 10 is preferably unitarilymolded from a thermoplastic material, and includes a proximal end 36, adistal end 38 and a lumen 40 extending axially therethrough. Proximalend 36 of blunt cannula 12 is configured for threaded engagement withthread 34 of luer collar 32. Distal end 38 of blunt cannula 12 iscylindrical and defines an external diameter "a". Distal end 38 also isconfigured for mating with an intravenous fitting having a pre-slitseptum to enable delivery of fluid medication from chamber 24 of syringebarrel 20 to a patient.

Vial access spike 14 also is preferably unitarily molded from athermoplastic material, and includes a proximal end 42, a distal end 44and a passage 46 extending axially therethrough. Portions of passage 46adjacent proximal end 42 are disposed in releasable fluid-tightengagement over distal end 38 of blunt cannula 12a, shown in FIG. 2.Passage 46 is cylindrical and defines an internal diameter "b" adjacentproximal end 42 of vial access spike 14 which is substantially equal tothe external diameter of blunt cannula 12 adjacent distal end 38. Distalend 44 of vial access spike 14 includes a beveled tip 48 which issufficiently sharp to be driven through the rubber stopper of a vial, asexplained and illustrated further herein. However, beveled tip 48 ispreferably not sufficiently sharp to penetrate skin upon incidental oraccidental contact.

Vial access spike 14 further includes a cap 50 articulated to a hinge 52which is joined to spike 14 at a location near proximal end 42. Cap 50is dimensioned to be telescoped over proximal end 42 of vial accessspike 14 for sealing substantially fluid-tight engagement. As shown inFIGS. 1-4, hinge 52 is an over center hinge with a first hinge 54 whichdefines an axis of rotation of cap 50. Over-center hinge 52 furtherincludes a second hinge element 56 which defines a rotational axisparallel to, but spaced from the rotational axis of first hinge 54.Second hinge 56 is resiliently deflectable at elbow 57 and is configuredto be in an unbiased condition in the fully open position of cap 50, asshown in FIGS. 1-3, or in the fully closed position as shown in FIG. 4.However, second hinge element 56 is biased at intermediate positions.The resiliency of second hinge element 56 therefore will assist anyopening or closing forces exerted by a user and will urge cap 50 towarda fully opened or fully closed position.

Alternate hinge 52a, as shown in FIG. 5, defines a tether. The tetherperforms the function of retaining cap 50 near proximal end 42 of spike14. However, the tether does not assist the opening or closing of cap50.

Shield 16 is preferably formed from a thermoplastic material, andincludes an open proximal end 60 and a distal end 61 which preferably isclosed. A passage 62 extends into proximal end 60 and defines an insidediameter "c" which is substantially equal to outside diameter "d" ofvial access spike 14 adjacent proximal end 42 thereof. Thus, proximalend 60 of shield 16 can be removably frictionally engaged over theentire vial access spike to prevent inadvertent contact with andcontamination of vial access spike 14. Proximal end 60 of shield 16 isfurther characterized by a slot 63 which is dimensioned to surroundhinge 52, and to thereby permit full seating of shield 16 over vialaccess spike 14.

Filling device 10 may be packaged and sold in a pre-assembled conditionas shown in FIG. 2. More particularly, proximal end 42 of vial accessspike 14 is frictionally engaged over distal end 38 of blunt cannula 12,while shield 16 may be frictionally engaged over at least portions ofvial access spike 14. Alternatively filling device 10 and blunt cannula12 may be packaged and sold in a premounted condition on hypodermicsyringe 18. In this latter embodiment, shield 16 preferably isdimensioned for releasable frictional engagement over outercircumferential portions of luer collar 32. Also, vial access spike 14and shield 16 may be sold assembled with the cap sealing the proximalend of the spike.

Filling device 10 is used with proximal end 36 of blunt cannula 12threadedly engaged to luer collar 32 of syringe barrel 20. Shield 16 isremoved shortly prior to use. Plunger 26 may then be moved proximally todraw into syringe barrel 24 a volume of air approximately equal to thedesired dose of medication. Beveled tip 48 of vial access spike 14 maythen be driven through rubber stopper 64 of vial assembly 66. Plunger 26is then moved distally to urge the air from syringe chamber 24 into vial66.

Hypodermic syringe 18 and vial 66 are inverted, as shown in FIG. 5, suchthat liquid medication 68 covers the portion of passage 46 of vialaccess spike 14 adjacent distal tip 48 thereof Plunger 26 is then movedagain in a proximal direction to draw into chamber 24 the required doseof liquid medication 68. Syringe 18 and vial assembly 66 are theninverted again such that vial assembly 66 is gravitationally belowsyringe 18. Syringe 18 and blunt cannula 12 then are separated from vialaccess spike 14 and vial 66. Syringe 18 and blunt cannula 12 may then beused in the standard manner as explained above. Vial access spike 14 canremain in rubber stopper 64 of vial 66 to enable subsequent access tomedication 68. Medication 68 is sealed from the environment by rotatingcap 58 about hinge 52 and into sealing engagement with proximal end 42of vial access spike 14. Remaining medication 68 in vial 66 can beaccessed subsequently by hingedly rotating cap 50 away from proximal end42 of vial access spike 14. This subsequent access can be achieved witha conventional prior art hypodermic syringe having a blunt cannula.

As best illustrated in FIG. 6 blunt cannula 12 and vial access spike 14are preferably connectable to each other by an interference frictionalfit between the outside diameter of the blunt cannula and the insidediameter of passageway 46 of the vial access spike. The preferred bluntcannula is integrally molded of one piece of thermoplastic material.However, the blunt cannula can be made with a plastic hub and a separateblunt cannula made of a rigid material such as stainless steel joined tothe hub by an adhesive or other suitable means. Lumen 40 of the bluntcannula also includes frusto-conically shaped proximal portion 41suitable for frictionally engaging standard luer slip, as illustrated inFIG. 7, or locking luer-type syringes, as illustrated in FIG. 1.

FIG. 7 illustrates a blunt cannula 12 aligned for assembly to syringe18A having frusto-conically shaped elongate tip 28A which is adapted tofrictionally and removably engage the frusto-conically shaped portion 41of the lumen of the blunt cannula. The blunt cannula of the presentinvention is preferably capable of being used with locking luer typesyringes, such as syringe 18, and luer slip type syringes, such assyringe 18A.

FIG. 8 shows another embodiment of the present invention wherein syringe70 includes integrally molded blunt cannula 12B having lumen 40Bextending therethrough and in fluid communication with chamber 24B ofthe syringe barrel. This embodiment of the invention works substantiallyidentically to the embodiments of FIGS. 1-7 except that the cylindricalblunt cannula cannot be separated from the syringe barrel.

While the invention has been described with respect to certain preferredembodiments, it is apparent that various changes can be made withoutdeparting from the scope of the invention as defined by the appendedclaims. For example, the blunt cannula of the syringe filling device maybe permanently mounted to a hypodermic syringe or integrally molded aspart of the syringe barrel. Additionally, the releasable engagementbetween the vial access spike and the blunt cannula may take forms otherthan the frictional engagement described and illustrated above. Stillfurther, a metallic blunt needle cannula may be used with the vialaccess spike.

Adverting to FIGS. 9-21, a fluid transfer device 120 for accessing fluidfrom vials and ampoules comprises a cannula assembly 121 including acannula 122 having a proximal end 123, a distal end 125 and a lumen 127therethrough. A hub 128 having an open proximal end 129 and a distal end131 joined to proximal end 123 of the cannula so that lumen 127 is influid communication with the open proximal end of the hub. Hub 128preferably includes radial projection 132 for engaging the locking luertype collar of a syringe barrel or other fluid delivery device, as willbe explained in more detail hereinafter. In this preferred embodiment,distal end 125 of the cannula includes a blunt tip 133, and the cannulaand the hub are integrally formed of a thermoplastic material. However,the cannula and the hub can be separately formed and attached throughvarious manufacturing processes with adhesives such as epoxy beingpreferred.

A filling straw 134 includes a proximal end 135, a distal end 137, and apassageway 138 therethrough. Filling straw 134 includes a housing 139 atproximal end 134 and a needle portion 141 at distal end 137 and a shaftportion 143 therebetween. The housing includes a cavity 144 in itsproximal end in fluid communication with passageway 138. The distal endof needle portion 141 includes cutting edge 145 for piercing a vialstopper.

The cutting edge is preferably sharp enough to pierce a vial stopper butnot as sharp as a needle cannula used for human injection. A point orcutting edge which is sharp enough for vial piercing and not sharpenough for human injection is evidenced in many I.V. therapy devicessuch as spikes or cannula for use with vials having pierceable stoppers.In this embodiment, needle portion 141 is made of metal such asstainless steel and can be held to the shaft portion using variousmanufacturing methods with adhesives such as epoxy being preferred. Ametal needle portion offers the advantage of high strength and smalldiameter to reduce penetration forces as the needle portion enters thevial stopper. It is also within the purview of the instant invention tohave the needle portion and the shaft portion integrally formed of asingle material such as thermoplastic. In either case, it is preferredto have a shoulder 147 between the shaft portion and the needle portionto limit the depth of penetration of the needle into a vial stopper.Also, the visual appearance of the short needle portion, the pronouncedshoulder and the relatively dull cutting edge communicate to the userthat this straw is not intended for injection and helps assure thatthere will not be a mistaken attempt to use it for human injection.

The present invention includes means for releasably engaging the cannulaassembly with the housing so that the open proximal end of the hub is influid communication with the passageway of the filling straw and thecannula is within the cavity or in the passageway, as best illustratedin FIG. 10. This connection should be relatively tight since fluid willbe drawn through the straw and the cannula assembly into a syringe orother fluid delivery device. The means for removably engaging a cannulaassembly to the housing can be accomplished by numerous structure suchas threads, complementary projections and recesses and the like, with africtional interference fit between interior surface 149 of the housingand exterior surface 150 of the needle hub being preferred. Accordingly,the housing and the hub can be releasably engaged and disengaged bymoving the housing and the hub toward each other or away from each otherin an axial motion. As will be explained in more detail hereinafter itis preferred that rotational force applied to the straw, through thehousing, can be transmitted to the hub for engaging and disengaging thehub and a syringe barrel. This ability to transfer torque from the strawto the cannula assembly can also be accomplished by the interference fitbetween interior surface 149 and the housing and exterior surface 150 onthe hub. However, additional structure can be provided to facilitate thetransfer of torque from the straw to the cannula assembly. In thispreferred embodiment, axial ribs 151 on the hub can engage axial ribs152 in the housing to transfer torque from the straw to the cannulaassembly.

A shield 155 includes an open proximal end 157, a distal end 158 and aside wall 159 therebetween defining a recess 161 and the shield. Shield155 is removably connected to filling straw 134 so that the needleportion and preferably the shaft portion of the straw are within therecess.

Numerous structures can be used to achieve the removable connectionbetween the shield and the straw such as threads, projections andrecesses to accomplish a snap-fit arrangement, and interference fits. Inthis preferred embodiment, interior proximal surface 162 in the shieldfrictionally engaged exterior surface 163 on the housing. Accordingly,axial force may be used to remove and re-install the shield on thestraw. Interior surface 162 and exterior surface 163 are preferablyfrusto-conically shaped to provide smooth frictional engagement. It isan important feature of this preferred embodiment that interior proximalsurface 162 of the shield also releasably engages exterior surface 150on the hub so that the shield can be used to shield the straw or, whenthe straw is removed, to shield the cannula assembly. This is animportant feature because it allows different methods for using thefluid transfer device of the instant invention, depending on thepreference of the user.

The fluid transfer device of the present invention is suitable for usewith fluid delivery devices such as syringes. For the purpose ofillustration, fluid transfer device 120 is connected to a hypodermicsyringe 170 comprising a syringe barrel 171 having a distal end 173, aproximal end 174 and a circular side wall 175 defining a chamber 176 forretaining fluid. Volume measuring indicia 172 are on the barrel formeasuring the dose of liquid to be delivered. The distal end of thesyringe barrel is connected to hub 128 so that the lumen of cannula 122is in fluid communication with chamber 176 of the syringe barrel. Inthis embodiment, distal end 173 of the syringe barrel includes afrusto-conically shaped tip 177 having a conduit therethrough whichprovides a fluid path between the cannula and the chamber. Thefrusto-conically shaped tip of the syringe barrel frictionally engages apreferably frusto-conically-shaped surface 130 in open proximal end 129of the hub. The distal end of the syringe barrel also preferably, butnot necessarily, includes a locking luer-type collar 179 concentricallysurrounding tip 177. The luer collar has an internal thread 180 whichengages the radial projection 132 on hub 128 to hold it securely to thebarrel. It is within the scope of the present invention to includevarious hub configurations to attach to a variety of other medical fluidhandling devices. The hub configuration described hereinabove, having afrusto-conically shaped interior cavity, reflects one of these manypossibilities. Many syringes and fluid handling devices, such asstopcocks and adapters, and other fluid handling devices contain luerslip and locking luer type fittings to which a hub having afrusto-conically shaped interior cavity will properly engage. It iswithin the purview of the present invention to provide a fluid transferdevice wherein the cannula assembly is integrally molded with thesyringe barrel.

A stopper 182 is positioned in chamber 176 in sliding fluid-tightengagement with circular side wall 175. A rigid elongate plunger rod 183is connected to the stopper and extends proximally through the openproximal end of barrel 171. The stopper and the plunger rod can be madeof one-piece unitary construction. Force applied to the plunger rodcausing sliding movement of the stopper in a proximal direction drawsfluid through conduit 178 into chamber 176. Conversely, sliding movementof stopper 182 in a distal direction urges fluid from chamber 176through conduit 178.

The fluid transfer device 120 of the present invention, coupled with afluid delivery device, such as a hypodermic syringe 170, can be used toaccess fluid in a vial or an ampoule and deliver said fluid to theinjection site of an I.V. set or catheter. As illustrated in FIG. 14,the fluid transfer device 120 can be used with syringe 170 to accessinjectable liquid or medication, such as fluid 185, contained within avial 186 having a pierceable stopper 187. The fluid is accessed bypiercing stopper 187 with needle portion 141 of filling straw 134.Shoulder 147 between needle portion 141 and shaft portion 143 on thefilling straw will limit the penetration of the needle portion into thevial. In the preferred embodiment the needle portion is approximately 10mm long and has a diameter of about 1.3 mm. Initially, an volume of airapproximately equal to the desired dosage is injected into the vial. Thevial is then inverted, as illustrated in FIG. 14, and the fluid iswithdrawn into the syringe by action of the plunger in a proximaldirection to urge fluid 185 from the vial 186 through passageway 138 ofthe filling straw, the lumen of the cannula and into the chamber 176 ofthe syringe barrel. The user will compare the axial position of theplunger with volume measuring indicia 172 on the cylindrical side wallto insure that the desired dose is obtained. It can be seen that thelevel of fluid 185 in the vial will gradually decrease as fluid is drawninto the chamber of the syringe barrel. Shoulder 147 keeps the distalend of the needle portion close to the stopper to make it easy towithdraw almost all of the liquid from the vial. Also, the short lengthof the needle portion coupled with the shoulder and the larger shaftportion sends a clear message to the medical practitioner that thisdevice is not intended for injection into humans.

As best illustrated in FIG. 15 the fluid transfer device of the presentinvention can also be used to withdraw fluid 185 from ampoule 191. Asnoted above, at the time of use the neck portion of the ampoule issnapped or severed leaving an open neck 192. Because the ampoule doesnot have an elastomeric seal it is not inverted during the transfer offluid from the ampoule to a hypodermic syringe. Accordingly, a longfilling straw, capable of reaching toward the bottom or the sides of theampoule is required. For this purpose, shaft portion 143 of the fillingstraw is provided. The long shaft portion in conjunction with the needleportion enables the fluid transfer device of the present invention toeffectively remove liquid from an ampoule. In the preferred embodimentthe shaft portion is approximately 15 mm long and has an outsidediameter of about 3 mm. As with the vial, fluid is withdrawn from theampoule into the chamber of the syringe through action of the plunger sothat fluid is drawn through the passageway in the straw, the lumen ofthe cannula assembly and into the chamber.

Referring to FIGS. 9-21, with particular emphasis on FIGS. 16-21, it canbe seen that there are two separate methods which can be used to delivermedication from the syringe to the injection site through an I.V. set orother catheter device having an injection site. The first method, asillustrated in FIGS. 16, 17 and 21. In this first method, after thesyringe is filled with fluid from a vial or ampoule or other source,shield 155 is placed over filling straw 134 so that the shield isremovably connected to the straw and needle portion 141 and shaftportion 143 are contained within recess 161 of the shield. This is thesame assembly as existed at the beginning of the filling process. Inthis preferred embodiment, engagement between the shield and the strawis accomplished by axial motion which causes structure on the openproximal end of the shield to engage the housing on the filling straw.The filled syringe is then delivered to the point of use. At the pointof use, the user will remove the assembly of the shield and straw fromthe cannula assembly by grasping the straw, preferably at raised portion136 on the straw, and applying an axial force to remove the straw fromthe cannula assembly, as illustrated in FIG. 17. Since the cannulaassembly is attached to the syringe through the locking luer collar, theconnection between the cannula assembly and the syringe barrel isstronger than the frictional engagement between the filling straw andthe cannula assembly, so that the actual force applied will not removethe cannula assembly from the syringe. Depending on the structures ofthe various parts, the forces can be balanced so that the desired resultis obtained with respect to removing components. The syringe is nowready for delivering medication, as will be described hereinafter inmore detail.

The second method for using the fluid transfer device of the presentinvention, as best illustrated in FIGS. 18-21, requires the user toremove filling straw 134 immediately after the syringe is filled withfluid from a vial or ampoule by grasping the filling straw, preferablyby enlarged portion 136, and applying an axial distal force to the strawto remove it from the cannula assembly. Shield 155 is then placed overthe cannula assembly, as illustrated in FIG. 19 to protect the cannulauntil the time of use. The second method is possible because hub 128 ofthe cannula assembly and housing 139 of the filing straw have similarexterior shapes so that shield 155 can engage either the hub or thehousing. In this preferred embodiment the engagement is frictional andengagement and disengagement can be accomplished by applying axialforces. At the time of use, as illustrated in FIG. 20 shield 155 isremoved from the cannula assembly by applying a distal axial force.

The preferred embodiment of the fluid transfer device of the presentinvention includes a cannula having a blunt distal end for use with I.V.sets or other catheter devices having injection sites with pre-slitseptums. Specifically, as illustrated in FIG. 21, an I.V. set 195 caninclude a housing 197 having a hollow interior conduit 198 and aflexible tube 199 connected to the vascular system of the patient,usually through a catheter. Housing 197 also contains flexible tube 196which is connected to a source of I.V. fluid. Housing 197 also includesport 200 having a conduit 201 therethrough in communication with thehollow interior. A septum 203 covers the end of the conduit or aspositioned within the conduit. The most common ports are covered bypierceable septums or pre-slit septums and are known in the art andsometimes referred to as "PRN" from the Latin pro re nata meaning "asthe need arises." The septum is preferably made of rubber or anotherelastomeric material which permits insertion of a sharp needle cannulain order to infuse fluids into or to withdraw fluids from the catheter.Upon withdrawal of the needle cannula, the septum seals itself Asillustrated in FIG. 21, septum 203 is a pre-slit septum having a slit204 therein. Septum 203 effectively seals conduit 201 from the exteriorof the housing. However, access to the conduit can be achieved bypressing blunt tip 133 of cannula 122 against the area of the septumcontaining slit 204. Gentle force applied to the syringe assembly in anaxial direction will cause the blunt distal end of the cannula to enterthe conduit through the slit which is forced open by the blunt cannula.Upon removal of the blunt cannula from the conduit, the slit portion ofthe septum automatically seals itself. Since housing 197 is connected tothe patient's vascular system medication can be given to the patientthrough the PRN port without additionally piercing the patient's veinor, in this case, without the use of a sharp needle.

It is an important feature of the present invention that the entireprocess of filling the syringe from a vial or ampoule with a fluid, suchas an injectable liquid or medication, and the delivery of this fluid tothe patient can be accomplished by using the cannula assembly of thepresent invention alone and without the use of any injection needles.The most common prior art way to withdraw medication from a vial with apierceable septum is to attach a standard hypodermic needle assembly,illustrated in FIG. 23, to a hypodermic syringe. The fluid is drawn intothe syringe barrel and then the needle is discarded and a blunt cannulais attached to the syringe. This additional step creates an opportunityto an accidental needle stick and requires the presence of some form ofdisposal system. Wherein the present invention, in its preferredembodiment, does not use a standard needle and does not require adisposal step since all of the components of the fluid transfer devicecan stay with the syringe until the time of use, at which time, allcomponents are suitably disposed of. Also, the present inventionprovides a fluid transfer device which allows for filling a syringe anddelivering the medication to the patient without the use of a sharpinjection cannula.

FIG. 22 illustrates an alternative cannula assembly 221 including ametal cannula 222, preferably made of stainless steel. Cannula 222includes a proximal end 223 and, distal end 225, having a lumentherethrough. Distal end 225 also includes blunt tip 233. Cannulaassembly 221 functions substantially as cannula assembly 121 except thatthe cannula is made of metal. Stainless steel cannula are desirablebecause of their great strength advantage over thermoplastic cannulawhich allows such cannula to be made in smaller outside diameters and alarge lumen diameter while still having substantial strength.

FIG. 23 illustrates a prior art needle assembly 321 which is commonlyused to inject medication into a patient and for transferring fluidthrough pierceable septums such as septums found in a medication vialsand I.V. sets. Needle assembly 321 includes needle cannula 322 having aproximal end 323, a distal end 325 and a lumen therethrough. Distal end325 further includes a sharp point 333 capable of piercing skin,flexible stoppers and septums.

The preferred embodiment of the fluid transfer device of the presentinvention includes a cannula assembly having a blunt cannula for usewhich allows the use of one device for filling a syringe through a vialor ampoule and delivering the fluid from the vial or ampoule through apre-slit septum of an I.V. set or other catheter device. Accordingly,the preferred embodiment is a needleless system for filling anddelivering injectable fluid which does not require a sharpened needlecannula or an additional step of disposing of such cannula after thesyringe is filled. However, it is within the purview of the presentinvention to include a fluid transfer device which contains a needleassembly having a needle cannula with a sharpened distal tip such asneedle assembly 321. In usages where a pre-slit septum is not availablein the catheter or I.V. set, a sharpened steel needle cannula must beused. However, even with a needle assembly having a sharpened needlecannula, the fluid transfer device of the present invention offers aclear advantage over the prior art in that the needle assembly stayswith the syringe from the time of filling through the time of injectionand there is no additional step of removing a sharpened needle cannulafrom the syringe after filling the syringe and no additionalcomplications regarding the disposal of the sharpened needle cannula inthis intermediate step. Also the needle cannula is protected from damageduring the filling procedure.

FIGS. 24 and 25 illustrate an alternative fluid transfer device of thepresent invention. The fluid transfer device of FIGS. 24 and 25functions substantially the same way as the fluid transfer device ofFIGS. 9-20 except that structure is provided so that the removal of thefilling straw from the cannula assembly requires a rotational motion.Specifically, alternative fluid transfer device 420 includes a cannulaassembly 421 having a cannula 422 and a hub 428. Hub 428 furtherincludes a locking luer collar 424 having an internal thread 426.Filling straw 434 includes a housing 439 having a radial projection 440configured to engage internal thread 426 of luer collar 424.Accordingly, attachment of the filling straw to the cannula assembly isaccomplished by a rotational motion. A shield 455 is removably connectedto the straw. The straw and the shield are configured so that the shieldcan be removed and reconnected to the straw through axial motion of theshield with respect to the straw. This alternative embodiment of thepresent invention offers a distinct advantage to the user since theshield is removable from the straw through axial motion and the straw isremovable from the cannula assembly through rotational motion furtherassuring that the user will not accidentally remove one component whenhe or she intends to remove another.

FIG. 26 illustrates an alternative structure of the fluid transferdevice of the present invention wherein the cannula or the cannulaassembly is integrally formed with a syringe barrel. Specifically,cannula assembly 521 which includes cannula 522 and hub 528 isintegrally molded with syringe barrel 571 so that the cannula is notremovable from the syringe barrel. Other than this feature the syringeand blunt cannula function substantially the same way as the embodimentillustrated in FIGS. 9-21.

FIGS. 27-28 illustrate an alternative fluid transfer device 600. Thisfluid transfer device 600 is intended for use in applications where aseparate cannula assembly is not required. Fluid transfer device 600includes a filling straw 634 having a proximal end 635, a distal end 637and a passageway 638 therethrough. The straw includes a housing 639 atsaid proximal end, a needle portion 641 at said distal end, and a shaftportion 643 therebetween. The needle portion and the shaft portion arepreferably integrally molded of thermoplastic material. The housingincludes a preferably frusto-conically shaped cavity 644 in its proximalend in fluid communication with passageway 638. A cutting edge 645 atthe distal end of the needle portion is provided for piercing a vialstopper. A shield 655 having an open proximal end 657, a distal end 658and a side wall 659 therebetween defining a recess 661 in the shield.The shield is removably connected to the straw so that the shaft portionand the needle portion of the straw are preferably contained within therecess. A syringe 670 having an elongate cylindrical body 671 defining achamber 676 for retaining fluid, an open proximal end, a distal end 673and a frusto-conically shaped tip 677, extending from the distal end andhaving a tip passageway 678 therethrough in fluid communication with thechamber. The tip is positioned within cavity 644 of housing 639 so thatchamber 676 is in fluid communication with passageway 638 of the fillingstraw. Cavity 644 in the housing includes a frusto-conically shaped wall646 configured to frictionally engage the frusto-conically shaped tip onthe syringe barrel. There are needleless systems comprising valves andspecial fittings which are designed to accept the standardfrusto-conically shaped tip of a hypodermic syringe barrel. With thesesystems a separate cannula assembly is not necessary since the tipportion of the syringe barrel acts as the cannula in the system. In allother respects the embodiment of FIGS. 27 and 28 function substantiallythe same as the embodiment of FIGS. 9-20 with the exception that thefluid is delivered through the tip of the syringe into the fluidreceiving device which could even be a pre-slit septum designed toaccept a standard syringe tip.

In this embodiment, it is preferred but not necessary that the syringeinclude a locking luer-type collar 679 having an internal thread 680.The proximal end of housing 639 includes radial projection 632 which isadapted to engage thread 680 to further enhance the connection betweenthe housing and the syringe barrel. In this embodiment, it is preferablethat shield 655 includes a radial projection 640 so that the shield canengage the luer collar when the filling straw is removed, so that afterfilling the syringe the straw may be discarded and the syringe tipreshielded with shield 655 for delivery to the point of use. In thealternative, the filled syringe with shielded straw attached may betaken to the point of use wherein the shield and the straw are removedtogether and discarded as described hereinabove in using the embodimentsof FIGS. 9-20.

FIGS. 29 and 30 illustrate an alternative fluid transfer device 720. Insome respects fluid transfer device 720 functions similarly to the fluidtransfer device of FIGS. 9-21. For the purposes of description, elementsin fluid transfer device 720 which are the same as elements in theembodiment of FIGS. 9-21 are given the same reference numerals. Fluidtransfer device 720 includes cannula assembly 121 having cannula 122 andhub 128. The filling straw 134 includes needle portion 141 havingcutting edge 145 at its distal end. The cannula assembly and the straware removably engaged. Fluid transfer device 720 is connected to syringe170 having an elongate cylindrical body 171 defining a chamber 176 forretaining fluid.

A shield 755 includes an open proximal end 757, an open distal end 758and a side wall 759 therebetween defining a recess 761 in the shield.The shield is removably connected to the filling straw so that shaftportion 143 and needle portion 141 are substantially contained withinrecess 761. A seal plug 756 includes a proximal end 760 and a distal end764. The seal plug has a distal position, as illustrated in FIG. 29,wherein the seal plug projects distally outwardly from distal end 758 ofshield 755 for telescoping movement from the distal position to aproximal position, illustrated in FIG. 30. The seal plug includes meansfor sealing the needle portion to prevent unpressurized fluid fromcommunicating between passageway 138 of the filling straw and theexterior of the shield, when the seal plug is in the proximal position.In this embodiment, means for sealing includes retention conduit 766extending distally from the proximal end of the seal plug. The retentionconduit includes an inside surface 767 for sealing engagement with theneedle portion of the filling straw when the sealing plug is in theproximal position as illustrated in FIG. 30. It is preferable to includea tapered portion 768 at the proximal end of the seal plug for guidingthe needle portion into the retention conduit when the seal plug isbeing moved from the distal position to the proximal sealing position.

In some applications it is preferred to provide structure, or toconfigure the components, so that in the normal use of the fluidtransfer device 720, seal plug 756 cannot be moved from its proximalsealing position to its distal position. In this embodiment means forpreventing the seal plug from moving from the proximal sealing positionto the distal position is provided by configuring the plug so that inthe proximal sealing position the plug is substantially within opendistal end 758 of shield 755. By being substantially within orcompletely within the open distal end of the shield, digital access tothe plug for the purposes of moving in a proximal direction is severelylimited or completely limited. Means for preventing movement of the sealplug from its proximal sealing position can also be provided byinteracting structure between the shield and the plug. Such structuremay have components on the inside or the outside of the shield dependingon the structure of the plug. Such structure can include projectionsand/or recesses on the shield to engage projections and/or recesses onthe seal plug when the seal plug is in said proximal position.

The seal plug may be held in its distal position through mechanicalinteraction between the shield and the seal plug such as interferingstructures, friction, threads or the like. In this embodiment, theshield includes inwardly directed projection 769 and the seal plugincludes recess 781. When the seal plug is in its distal positionprojection 769 is positioned in recess 781 holding the seal plug in itsdesired axial position with respect to the shield. The projection may beof any size from a discrete bump to a full annular ring, or a segmentedring depending on the structural shapes and the choice of materials forthe plug and the shield. Likewise, the recess in the seal plug can takea variety of configurations to appropriately mate with the projection inthe shield. Also, the structure can be reversed so that the projectionis on the seal plug and the recess is in the shield.

To move the seal plug to its proximal sealing position, the user canapply digital pressure to finger contact surface 790 at distal end 764of the seal plug. In this embodiment, as the seal plug moves proximally,tapered portion 768 guides, where necessary, the distal end of needleportion 141 into the retention conduit 766 of the seal plug. In thisembodiment, inside surface 767 of the retention conduit is configured tocontact the exterior surface of needle cannula 141 for a sealingengagement. The inside surface can be continuous as illustrated or someother sealing structure such as one or more inwardly projecting ringswhich provide a seal. Proximal motion of the seal plug with respect tothe shield may be limited by additional structure or by configuring thecomponents. For example, if the seal plug is completely within theshield, proximal motion of the seal plug, through digital applicationwill cease when the finger contact surface of the plug is aligned withthe distal end of the shield. In this embodiment further structure isprovided to limit the proximal motion of the seal plug with respect tothe shield. This structure includes protuberance 784 on the seal plugand ledge 788 in the shield. In its proximal sealing positionprotuberance 784 will contact ledge 788 to provide resistance to furtherproximal motion and feedback to the user that the seal plug is in theproximal sealing position. The physical engagement of the seal plug withrespect to the needle portion may be all that is needed to hold the sealplug in its proximal sealing position. Although not necessary, thisembodiment preferably includes additional structure for holding the sealplug in its proximal sealing position. This structure includes exteriorsurface 789 of the seal plug being larger than the space provided in theopen end of the shield at projection 769 so that there is a frictionalengagement between the seal plug and the shield as illustrated in FIG.30. All of the structures recited hereinabove for holding said seal plugin its distal position are within the purview of the present inventionfor holding the seal plug in its proximal sealing position.

In use, the fluid transfer device 720 is filled in the same mannerdescribed for the embodiment of FIGS. 9-21. After filling, the shield isre-installed over the straw. The user then applies digital pressure tofinger contact surface 790 of the seal plug to move the seal plug fromthe distal position, as illustrated in FIG. 29, to the proximal sealingposition, as illustrated in FIG. 30. At this point the entire fluid pathfrom chamber 176 in syringe barrel 171 through the passageway in theneedle portion of the straw is sealed to protect the contents from theenvironment and to help prevent unpressurized loss of the contents tothe environment. This feature allows the medication containing fluidtransfer device and syringe to be stored for a longer period of timethan an unsealed system such as the embodiment of FIGS. 9-21. This is animportant feature of this embodiment of the present invention.

FIGS. 31-33 illustrate an alternative fluid transfer device 820 which issimilar to the embodiment of FIGS. 27 and 28 with a shield and seal plugassembly which is similar, but not identical, to the embodiment of FIGS.29 and 30. For the purposes of illustration, fluid transfer device 820is connected to syringe 670 having an elongate cylindrical body 671defining a chamber 676 for retaining fluid, an open proximal end, adistal end 673 and a frusto-conically shaped tip 677, extending from thedistal end and having a tip passageway 678 therethrough in fluidcommunication with chamber 676. Filling straw 634 includes a proximalend 635, a distal end 637 and a passageway 638 therethrough. The strawis connected to tip 677 of the syringe so that passageway 638 is influid communication with chamber 676.

A shield 855 having an open proximal end 857, an open distal end 858 anda side wall 859 therebetween defining a recess 861 in the shield. Theshield is removably connected to the filling straw so that the shaftportion and the needle portion are contained substantially within therecess.

A seal plug 856 includes a proximal end 860 and a distal end 864. Theseal plug has a distal position wherein the seal plug projects distallyoutwardly from the distal end of the shield for telescoping movementfrom the distal position, as illustrated in FIG. 31, to a proximalposition, as illustrated in FIG. 32, wherein the seal plug seals theneedle portion to prevent unpressurized fluid communication between thepassageway and the exterior of the shield.

Although a wide variety of materials such as, natural rubber, syntheticrubber, thermoplastic elastomer and thermoplastic can be used tofabricate the seal plug of the present invention, softer materials suchas natural rubber, synthetic rubber and thermoplastic elastomers arepreferred for seal plug 856 of the present embodiment. In thisembodiment, the components are configured such that needle portion 641is long enough so that when seal plug 856 is in the proximal position,as illustrated in FIG. 32, the distal end of needle portion 641 isembedded in proximal end 860 of the seal plug. Depending on the shape ofthe cutting edge 645 of the needle portion and the configuration andmaterial of the seal plug, embedding the needle portion into the sealplug will cause the seal plug to sealingly engage the outside surface ofthe needle portion, occlude the passageway therethrough, as illustratedin FIG. 33, or both, to prevent unpressurized fluid communicationbetween the passageway and the exterior of the shield. Fluid transferdevice 820 is used in a similar manner to the embodiment of FIGS. 29 and30.

FIG. 34 illustrates an alternative fluid transfer device 920 which isattached to cannula assembly 521 which includes cannula 522 and hub 528which are integrally formed with syringe barrel 571. A filling straw 934includes a proximal end 935, a distal end 937 and a passageway 938therethrough. Filling straw 934 includes a needle portion 941 at itsdistal end and a shaft portion 943 between the needle portion 941 andproximal end 935. A cutting edge 945 at the distal end of the needleportion is provided for piercing a vial stopper. The cannula assemblyand the filling straw are removably engaged. A shield 955 has an openproximal end 957, an open distal end 958 a side wall 959 therebetweendefining a recess 961 in the shield. The shield is removably connectedto the filling straw so that the needle portion and substantially all ofthe shaft portion are contained within the recess.

A seal plug 956 includes a proximal end 960 and a distal end 964. Theseal plug has a distal position, as illustrated in FIG. 34, wherein theseal plug projects distally outwardly from distal end 958 of shield 955for telescoping movement from the distal position to a proximal positionwherein the seal plug seals the needle portion to prevent unpressurizedfluid communication between the passageway and the exterior of theshield.

In use, the syringe is filled using the filling straw, as generallydescribed hereinabove, and the shield is replaced as illustrated in FIG.34. The user can then apply a proximally directed force to fingercontact surface 990 on the seal plug to move the seal plug into theproximal sealing position.

What is claimed is:
 1. A fluid transfer device for accessing fluid fromvials and ampoules comprising:a cannula assembly including a cannulahaving a proximal end, a distal end and a lumen therethrough, and a hubhaving an open proximal end and a distal end joined to said proximal endof said cannula so that said lumen is in fluid communication with saidopen proximal end of said hub; a filling straw having a proximal end, adistal end and a passageway therethrough, said straw including a housingat said proximal end, a needle portion at said distal end and a shaftportion therebetween, said housing having a cavity in its proximal endin fluid communication with said passageway, a cutting edge at thedistal end of said needle portion for piercing a vial stopper, and saidcannula assembly and said filling straw being removably engaged so thatsaid open proximal end of said hub is in fluid communication with saidpassageway of said filling straw; a shield having an open proximal end,an open distal end and a side wall therebetween defining a recess insaid shield, said shield being removably connected to said filling strawso that said shaft portion and said needle portion are containedsubstantially within said recess; and a seal plug having a proximal endand a distal end, said seal plug having a distal position wherein saidseal plug projects distally outwardly from said distal end of saidshield for telescoping movement from said distal position to a proximalposition, said seal plug including means for sealing said needle portionto prevent unpressurized fluid communication between said passageway andthe exterior of said shield when said seal plug is in said proximalposition.
 2. The fluid transfer device of claim 1 wherein said means forsealing includes a retention conduit extending distally from saidproximal end of said seal plug, said conduit having an inside surfacefor sealing engagement with said needle portion when said sealing plugis in said proximal position.
 3. The fluid transfer device of claim 2wherein said seal plug includes a tapered portion at said proximal endfor guiding said needle portion into said retention conduit when saidseal plug is being moved from said distal position to said proximalposition.
 4. The fluid transfer device of claim 1 wherein said sealingmeans includes said needle portion being long enough so that when saidseal plug is in said proximal position said distal end of said needleportion is embedded in said proximal end of said seal plug.
 5. The fluidtransfer device of claim 1 wherein said seal plug is made of materialselected from the group consisting of natural rubber, synthetic rubber,thermoplastic elastomer and thermoplastic.
 6. The fluid transfer deviceof claim 1 further including means for preventing said seal plug frommoving from said proximal sealing position to said distal position. 7.The fluid transfer device of claim 1 wherein said open proximal end ofsaid shield is configured to releasably engage said hub when saidfilling straw is removed from said hub.
 8. The fluid transfer device ofclaim 1 wherein said distal end of said cannula includes a blunt distaltip.
 9. The fluid transfer device of claim 1 wherein said cannula andsaid hub are integrally formed of thermoplastic material.
 10. The fluidtransfer device of claim 1 wherein said cannula is formed of metal. 11.The fluid transfer device of claim 1 further including a syringe barrelhaving an elongate cylindrical body defining a chamber for retainingfluid, an open proximal end, a distal end and a tip extending from saiddistal end having a tip passageway therethrough in fluid communicationwith said chamber, said tip being positioned within said open proximalend of said hub so that said chamber is in fluid communication with saidlumen of said cannula.
 12. The fluid transfer device of claim 1 whereinsaid cannula assembly is integrally formed with a syringe barrel havingan elongate cylindrical body defining a chamber for retaining fluid, anopen proximal end and a distal end, said cannula extending from saiddistal end of said barrel and positioned so that said lumen of saidcannula is in fluid communication with said chamber.
 13. A fluidtransfer device for accessing fluid from vials and ampoules comprising:acannula assembly including a cannula having a proximal end, a distal endand a lumen therethrough, and a hub having an open proximal end and adistal end joined to said proximal end of said cannula so that saidlumen is in fluid communication with said open proximal end of said hub;a filling straw having a proximal end, a distal end, and a passagewaytherethrough, said straw including a needle portion at said distal endand a shaft portion between said needle portion and said proximal end, acutting edge at the distal end of said needle portion for piercing avial stopper, and said cannula assembly and said filling straw beingremovably engaged so that said open proximal end of said hub is in fluidcommunication with said passageway of said filling straw; a shieldhaving an open proximal end, an open distal end and a side walltherebetween defining a recess in said shield, said shield beingremovably connected to said filling straw so that said needle portionand substantially all of said shaft portion are contained within saidrecess; and a seal plug having a proximal end and a distal end, saidseal plug having a distal position wherein said seal plug projectsdistally outwardly from said distal end of said shield for telescopingmovement from said distal position to a proximal position wherein saidseal plug seals said needle portion to prevent unpressurized fluidcommunication between said passageway and the exterior of said shield.14. The fluid transfer device of claim 13 further including a syringebarrel having an elongate cylindrical body defining a chamber forretaining fluid, an open proximal end, a distal end and a tip extendingfrom said distal end having a tip passageway therethrough in fluidcommunication with said chamber, said tip being positioned within saidopen proximal end of said hub so that said chamber is in fluidcommunication with said lumen of said cannula.
 15. The fluid transferdevice of claim 14 wherein said open proximal end of said shield isconfigured to releasably engage said distal end of said syringe barrelwhen said filling straw is removed from said syringe barrel.
 16. Amethod for transferring injectable liquid including comprising the stepsof:(a) providing a syringe including a syringe barrel having an elongatecylindrical body defining a chamber for retaining fluid, an openproximal end, a distal end and a tip extending from the said distal endhaving a tip passageway therethrough in fluid communication with saidchamber, a stopper in fluid-tight slidable engagement inside said barreland an elongate plunger rod connected to said stopper and extendingproximally through said open proximal end of said barrel; (b) providinga syringe filling device comprising a cannula assembly including acannula having a proximal end, a blunt distal end and a lumentherethrough, and a hub having an open proximal end and a distal endjoined to said proximal end of said cannula so that said lumen is influid communication with said open proximal end of said hub; a fillingstraw having a proximal end, a distal end and a passageway therethrough,said straw including a, a needle portion at said distal end and a shaftportion between said needle portion and said proximal end, a cuttingedge on the distal end of said needle portion for piercing a vialstopper, said cannula assembly being removably engaged with said fillingstraw so that said open proximal end of said hub is in fluidcommunication with said passageway of said filling straw; a shieldhaving an open proximal end, an open distal end, and a side walltherebetween defining a recess in said shield, said shield beingremovably connected to said straw so that said shaft portion and saidneedle portion are contained within said recess; and a seal plug havinga proximal end and a distal end, said seal plug having a distal positionwherein said seal plug projects distally outwardly from said distal endof said shield for telescoping movement from said distal position to aproximal position wherein said seal plug seals said needle portion toprevent unpressurized fluid communication between said passageway andthe exterior of said shield; (c) connecting said syringe filling deviceto said syringe so that said tip is positioned within said open proximalend of said hub and said chamber is in fluid communication with saidcannula; (d) providing a vial having a pierceable septum and containingan injectable liquid; (e) removing said shield from said straw; (f)piercing said pierceable septum of said vial with said needle portion ofsaid filling straw to establish fluid communication between the interiorof the vial and the chamber of the syringe; (g) withdraw the desiredamount of injectable liquid from said vial into said chamber by movingsaid plunger rod in a proximal direction with respect to said barrel;(h) withdrawing said needle portion from said septum of said vial; (i)reconnecting said shield to said straw so that said shaft portion andsaid needle portion of said straw are contained within said recess ofsaid shield; and (j) moving said seal plug from said distal position tosaid proximal position to seal said needle portion.
 17. The method ofclaim 16 further comprising the steps of:(k) moving said syringe to anI.V. set having an injection site with a pre-slit septum; (l) removingsaid shield and said straw from said cannula assembly; and (m) advancingsaid syringe into said pre-slit septum so that said blunt tip of saidcannula pierces said septum and establishes fluid communication withsaid I.V. set; and (n) advancing said plunger so that said piston movessaid fluid from said chamber through said lumen into said I.V. set.